Volumetric Flask with White and Blue Balls: Demonstration of Microcanonical Ensemble of Small Populations

Abstract

The microstates of an isolated system indicate the different distributions of the energy of a system over the set of particles of the system. Microstates with the same (quantum states) occupation number form a configuration set. All microstates have the same probability of occurrence. Students determined the probability distribution of the configurations in a model experiment demonstrating the ergodic theory. The model experiment required a volumetric flask with white and blue plastic balls. The sequential order (repeated permutation) of the plastic balls in the neck of the flask corresponds to a microstate. The experiment was performed after the theoretical lecture.